Automatic telephone system



H. E. HERSHEY.

AUTOMATIC TELEPHONE SYSTEM.

APPLICATION FILED MAR. 10' 1916- Patented Apr. 27, 1920. I

n IIIHIIIIIIIHII' flTTOR/VEY H. E. HERSHEY.

AUTOMATIC TELEPHONE SYSTEM.

APPLICATION FILED MAR. 10, 1916.

1,338,370. Patented Apr. 27, 1920.

2 SHEETS-SHEET 2.-

UNITED STATES PATENT OFFICE.

HARRY E. HERSHEY, OF WHITEWATER, KANSAS, ASSIGNOR, T0 AUTOMATIC ELECTRICCOMPANY, OF CHICAGO, ILLINOIS, A CORPORATION OF ILLINOIS.

AUTOMATIC TELEPHONE SYSTEM.

Specification of Letters Patent. Patented Apr. 27, 1920.

J Application filed-March 10, 1916. Serial No. 83,250.

To-all whom it may concern:

Be it known that I, HARRY E. HERSHEY, a citizen of the United States ofAmerica, and a resident of Whitewater, Butler county, Kansas, haveinvented certain new and useful Improvements in Automatic- TelephoneSystems, of which the following is a specification.

My invention relates to automatic telephone systems and has particularreference to selective signaling methods in such automatic systems ascomprise poly-station lines. In these systems it is customary to providethose substations which are on the same line with ringers which areadapted to respond to ringing currents of different character. At theexchange, ringing cur- .rent generators of different character areprovided which in the course of the operation of the system maybeselectively associated with called lines at proper times to si nalwanted subscribers.

J y invention relates, more specifically, to the method employed at theexchange for accomplishing the afore-mentioned selective action wherebythe ringing current generator corresponding to a wanted substation my beselected; and as illustrated herein contemplates the use of thewell'known har- 'monicsignaling system, in which the ringing currentsdiffer in frequency, although other well known systems might equallywell be used.

In practising my invention I employ a single group of connector switchesfor each group of poly-stationlines. Each connector of the group isprovided with a relay for each separate frequency of ringing current andhas, in addition, a vertical row of contacts, one for each relay, and awiper adapted to engage these contacts 1n the vertical movement of theswitch. In the operation of my system, the connectors respond to threedigits instead of two. When the'first digit is received andthe connectorresponds thereto to raise its shaft, one of the frequency selectingrelays is. operated through the medium of the special wiper and verticalrow of contacts. After the first digit has been called the connector isautomatically released and is thenready for operation in response to theremaining two digits in the regular manner.

A further object of my invention is the provision in a connector switchof the above character of means whereby a calling subscriber, who isattempting to signal a second subscriber whose telephone has been takenare incorporated into automatic connector.

switches of wellknown type and construction toform a simple andeflicient apparatus.

To accomplish the foregoing and other useful ends my invention comprisesmeans which will be hereinafter set forth and fully explained, referencebeing had to the accompanying drawings, in which Figures 1 and 2, takenin order with the lines at the ends thereof in alinement, represent acomplete connection between a calling substation A and a calledsubstation A in a system embodying the principles of my invention.

Referring now to Fig. 1, the automatic substation A comprises the usualreceiver 2, transmitter 3, ringer 4 and condenser 5. Being an automaticsubstation, it is also provided with a suitable call sending mecha-vnism for controlling the automatic switches, which mechanism isrepresented diagrammatically by a pair of impulse springs 6 and 7 and animpulse wheel 8, which latter may be controlled by a dial provided withfinger holes in such a way that the impulse springs may be momentarilyseparated a number of times corresponding to the re spective digits ofthe number of the called subscriber. A substation of the above generaltype is shown in British patent to Martin, No. 1419 of 1910.

-All0tted to the line conductors ofsubstation A at the exchange is anindividual or line switch C, which maybe of the general type of lineswitch shown in British patent to R. W. James, No. 26,301 of 1906;being, however, of the particular compr ses among other details aplunger (not shown) attached'to the end of a socalled plunger arm 9which is controlled by 'type disclosed in British patent to T. G.Martin, No. 1419 of 1910.- This line switch full cut-off armature 15.The pull-in winding 11 operates both the plunger arm 9 and the armature15, while the cut-off or holding winding 12 is only strong enough tooperate the cut-off .armature 15 and to hold the plunger arm 9 in itsoperated position. When the lunger arm is operated, the plunger isforced into a bank of contact springs forcing the springs 16, 17 18 and19 into engagement, respectively, with the contacts 20, 21, 22 and 23.Although only one set of contacts (20-23) is shown, each line switch isprovided with a plurality of such sets, each set forming the terminal ofatrunk line leading to a connector switch. Each trunk line is connectedin multiple with the corresponding contacts of all the line switches ofthe group which is controlled by the master switch D. The switch C isinitially controlled b the subscriber through the medium 0 the linewinding 13, as will hereinafter be more explained.-

T e master switch D is of the same general ty e as that disclosed inBritish patent to R. James No. 26,301 of 1906; being, however, of theparticular type disclosed in British patent to T. G. Martin, No. 1419 of1910. The function of the master switch,

as is well known, is to maintain the plungers of all the idle lineswitches in. posi- Tion to engage the terminal of anidle trunk Theconnector switch His of the same general type of connector switchdisclosed in United States Letters Patent No. 815,17 6, granted March13, 1906, to Keith, Erickson, and Erickson, the circuits, however, beingmodified to adapt the switch to operate in a system in which the centraloffice apparatus is controlled by impulses delivered over the two sidesof the line in series, as shown in British patent specification No. 2270of 1914.

Among other details, the connector H- comprises a bank of contactsarranged in horizontal rows or levels, which contacts are adapted to beengaged by a set of wipers, 25, 26 and 27 carried upon a shaft (notshown) which has avertical movement controlled by the verticalmagnet 28and amtary movement controlled by the rotary magnet 29. The usual sideswitch comprising the wipers 30,31, 32 and33 is controlled by theprivate magnet 34 in the usual and well known manner. The operation ofthe various parts of the switch is controlled through the medium of theline relay 35.

The called line is provided with talking cur= rent through the so-calledback-bridge relay 36. The ringer relay 37 affords the meansby which rining current is applied, to the called line. cans for permitting theswitch to be restored to normal position, are provided in'the releasemagnet 38, which, upon 7 energizing, withdraws the retaining double-dogfrom the shaft and returns theside switch wipers to firstposition. Thesprings 39 and 40 engage their respectivecontacts only when the switchshaft has been raised one or more steps from its lowest position.

' The relays 41 and 42 are slow acting, that is,

slow to release their armatures upon deener 1z1ng.

so I

n accordance with my invention the .con-" nector H is provided with avertical row of k contacts adapted to be engaged by the wiper 24 carriedupon the same shaft as the wipers 25, 26, and 27 The contacts in thevertical row are spaced the same distance apart as are the levels in thehorizontal banks, so that if the wipers are raised opposite the firstlevel, the special wiper 24 will engage the lowest vertical contact,while, if the wipers are raised opposite the third level,

the wiper 24 will engage the third vertical contact, etc.

The connector H is provided, furtl1er-.

more, with a group. of relays indicated by reference characters 63, 163,263, and 363,

which relays are associated, respectively,

with the four contacts in the previously mentioned vertical contact row.Each of the relays 63, 163, etc., is associated alsowith a particularsource of ringing ourrent, which ringing current sources are indicatedby reference characters R,'R etc. At the upper right hand corner of Fig.1'

are shown two relays whose function is to connect the connector H withthe trafiic trunk conductors 99 and 199 at the proper time as will bemore fully explained hereinafter.

Relay 72 is bridged by the condenser 71, is provided with a slug ofcopper at one end of the core, and is adjusted to respond to directcurrent but not to alternating or ringing current. Relay ,87 is alsoprovided with a slug of copper at one end of the core and is so adjustedthat it is slow to attract its armature. Other well known devices may beused to cause relay 87 to respond slowly when its energizing circuit isclosed, the means shown being chosen with regard to simplicity ofillustration.

Referring now to Fig. 2, there is shown a poly-station line across theconductors 76 and 79 of which arebridged three substations indicated byreference characters A,

A and A. A fourth substation for which capacity is provided in mysystem, is assumed to have been taken out or denergi zed. Except forthpir ringers, the sub- In accordance with my invention each ringermovement is provided with a pair of contact springs, shown at 98 1nconnection with substation A, wh1ch areclosed intermittently in theoperation of the ringer to short circuit the condenser in seriestherewith.

For supplying current for operating and talking purposes I have shown abattery B having its positive terminal grounded. The

reference character Q indicatesa busy-signaling machine for supplying abusyi tone to a calling line in case of an-attempted connection with abusy line. 1

While I have shown in Fig. 1 the line switch C as having direct accessto the connector H, it will be understood by persons versed in the artthat selector switches may be interposed in order to increase thecapacity of the system. Selector switches which may be used aredisclosed in British patent to Automatic Telephone Mfg.v 00.,

.No. 2543 of 1914.

A general description of the apparatus having been given, it will now beexplained how connection can be established between the line ofsubstation A and the line of 3. called substation A. The number of thecalled substation will be assumed to be 122. Since the automaticswitching apparatus disclosed herein is in general well known in theart, and is described in the publications herein referred to, itsoperation will be explained in a more or less general manner.

When the subscriber at substation A removes his receiver preliminary tomaking a call, an energizing circuit is closed through the line winding13 of the individual switch C. The winding 13, upon energizing, closes acircuit through the pull-in winding 11 in series with the auxiliarywinding 14. The pull-in winding, upon energizing, attracts the plungerarm 9, to force the plunger into the bank of springs 16to 19. It alsooperates the cut-off armature 15, thereby disconnecting the line winding13 from the line. The armature 43 does not fall back immediately,however, owing to the fact duced in the short-cirouited winding 14.-

This slow action of the armature 43 allows 7 sufficient time for aholding circuit to be closed in the switch ahead for the cut-oil orholding winding 12. The engagement of springs 16 and 19 with contacts20and 23, respectively, extends the subscribers line to the line relay35 of the connector H. The line relay 35, thereupon energizes over acircuit extending from ground G. through the lower winding of relay 35,contact 23, spring 19 to and through substationl A, spring 16, contact20, and upper winding of relay 35 to battery B. The line relay35, uponener izing, closes a circuit through relay 41. elay 41, upon energizing,closes a holding circuit for the line switch 0,. This circuit may betraced from ground Gr through springs 45, contact 21 and spring 17 towire junction 46, thence one branch.

extends over the conductor 47 to the multiple connector private bankcontacts associated with the line switch C. The other branch extendsfrom the wire junction 46 throu h the holding winding 12 to battery B.he grounded private bank contacts prevent any connector from makingconnec-,

tion with the line of substation A whilethe line switch C is operated.

The calling subscriber now operates his calling device .for the firstdigit 1 of the called number, whereby the implse springs 6 and 7 areseparated once momentarily, thus breaking the circuit of the line relay35. The relay 41, being slow acting, does not denergize during themomentary inter-v ruptions of its circuit by the relay 35, andconsequently, each time the latter relay deenergizes, an impulse istransmitted to the vertical magnet28 over a circuit extending fromground G through contact springs 48 and 49, contact springs 50 and 51,relay 42, vertical magnet 28, and side switch wiper 30 (in firstposition) to battery 'B. The vertical magnet receives one impulse overthis circuit and operates to raise the switch shaft and-the wipers 25,26 and 27 opposite the first row or level of bank contacts, and at thesame time wiper 24 is brought into engagement with bank contact 52. Theshaft controlled contacts 39' and 40 are also closed at this time. Theslow acting relay 42 is maintained in its energized positioncontinuously while impulses are being transmitted to the vertical magnetand in its ener ized position closes a circuit from ground 4 throughcontact springs 53 and 54, and private magnet 34 to batter B. When relay42 'deenergizes, at the end 0 the impulse or series of impulses, thecircuit of the private magnet is broken and the side switch wipers moveto second position in the well known manner. They are restoredinstantly, however, by the release magnet 38 which is included in onebranch of a divided circuit, closed by relay 42 an instant after theprivate magnet circuit is broken, and which may be traced as follows:ground at G, contact springs 55, contact springs 56 contact springs 57,contact springs '58, an

contact springs 59 to wire junction 124 where the circuit divides," onebranch e tending by way of release magnet 38 an ofi normal contact 40 tobattery B, and the release magnet, upon energizing, locks itself tactsprings 60 and operates to restore the other branch extending by way ofwiper 24,

bank contact 52, contact springs 61 and 62, v

and winding of relay 63 to battery BQ The by way of off normal contact39 and considesw'itch wipers and shaft. to normal'position after whichits circuit is opened at the oil normal contacts. Relay 63, uponenergizing, closes a locking circuit for itself a over thefollowingpath: ground at G, con- 20 tact springs 45, contact springs 64and 62 and winding of relay 63 to battery B. Further results of theoperation of relay 63 are the connection of ground at G 'to one side ofrelay 72 (of no consequence until' later), the connection of oneterminal of the generator R to a lead extendin to ringing relay 37, andthe breaking of t e previously described divided circuit extending fromground at G.

The calling subscriber now operates his calling device for the seconddigit 2 in response to which the connector line rela operates totransmit two impulses throng the vertical magnet 28, whereby the shaftwipers are raised opposite the second row or level of bank contacts, Therelay 42 operates in response to the impulses for this d git in the samemanner as for the previous digit to cause the private magnet to beenergized. After the last impulse has been delivered to the verticalmagnet, the relay 42 denergizes and opens the circuit of the privatemagnet 34, which, upon deenergizing, permits the side switch to passfrom first to second position. The movement of the side switch'wiper' 30from first to. second position transfers the battery connection from thevertical magnet 28 to the rotary magnet 29. The circuit previouslyclosed .at contact springs59 will not be closed at "this time owing tothe fact that ground at G has been removed fromthe circuit at springs55. i

The calling subscriber now operates his calling device for the lastdigit 2,'in re-. sponse to which the connector line rela operatestotransmit two impulses throng therotary magnet 29, whereby the shaftwipers are rotated ontothe contacts .of the desired line. This circuitextends from ground G through contact springs 48 and 49,'contact springs50 and 51, relay 42, con-.

tact springs 65, rotary magnet 28, and side switch wiper 3O (in secondposition) to inseam p I battery B. Therelay 42 operates in response tothe impulses for this digit in the same manner as for the previous digitto cause the private magnet 34 to advance the side switch to thirdposition.

By the engagement of the side switch wipers. 31 and 32 with their thirdposition contact points, the line: connection is ex-' tended through toline Wipers 25 and 27. Upon the" engagement of the side switch wiper 33with its third position contact cut-ofi winding 66 of the called'lineswitch point, a circuit is completed through the C'.. This circuitextends from ground G .-through side switch wiper 33 .(in-thirdposition),- private wiper 26, bank contact 67,

and cut-offwindin 66 to battery B. The

cut-ofi winding 0 the called .line switch, I upon energizing, operatesto disconnect the line conductors 79- and 76 from' their 'con nectionsin line switch C and to connect line conductor 79 to the normalconductor extending to connector bankcontact 80; The

connection of ground-Gr with the multipleconnector private bank contactsof the called line, such as contact 67, prevents the called ,line frombeing seized by some other 0011-.

nector switch. By the engagement of the side switch wiper 30 with itsthird position contact point, the circuit of the ringer relay 37 isclosed. This circuit extends'from.

ground Gr through interrupter 68, ringer relay 37, contact springs 69,and side switch wiper 30 (in third position) to battery B. Y

The ringer relay 37 is energized interm t- 1 tently through the mediumof theinterrupter 68 and operates to disconnect the calling line fromthe called line and to bridge the ringing current generator R across thecalled line to'signal the called subscriber. The-circuit of'the ringingcurrent extends from groundG through contact springs 7 O, condenser 71inparallel with relay 72, contact springs 73 and '7 4, Wiper 27, bankcontact 75, line conductor 76, through ringer 77 and condenser 78 inparallel with'the other ringers and condensers upon the line, lineconductor 79, bank contact 80, wiper 25, contact springs 81 and 82-,contact springs 83, ringing current generator R and battery B toground". Ringing current over the above path actuates the ringer atsubstation A, Y

ener 'zed.. V

en the side switch wiper 30 passed to its third position and beforerelays 37 and 72 have had time to operate, a circuit including relay 87is completed over the following path: ground at G, interrupter 68,contact springs 69, contact springs. 84, contact springs 85 and 86,winding of relay 87, and side switch wiper 30 (in third position) tobattery B. The function of the relay 87, as before mentioned, is toconnect the calling subscriber with an operator should a number becalled for which there is no corresponding substation. It will be seen,

therefore, that relay 87 should 'be made slow to energize so as to allowtime for the. relay 72 to operate and open the. above described circuitin case a number is called for which there is a corresponding connectedsubstation. In the present case, where substation A is being signaled,relay 72 operates to open contact springs 84 before relay 87 has hadtime toenergize.

When the called subscriber removes.,his-

receiver in response to the ringing of his bell, energizlngcircult iscompleted in the well known manner for the back bridge re-.

lay 36 (ringing relay 37 being momentarily deenergized). Upon attractingits arma-' ture, relay 36 completes, an energizing circuit for the ringcut-off relay 88, which latter, upon attracting its armature, looksitself from ground at G and at the same time opens the conductor fromthe interrupter 68.

A complete talking circuit has now been established and the calling andcalled subscribers may converse without further efiort. Current for thetransmitter at substation A is supplied through the windings of thedouble wound line relay 35, while current V for the transmitter atsubstation A is supplied through the windings of the double woundanswering bridge relay 36. The voice currents take the path shown in theheavy lines which is thought to be clear without further explanation.

. When the conversation is finished, both subscribers will, hang uptheir receivers. When the receiver at substation A is hung up, theenergizing circuit of the line relay. 35 'is broken. Following thedeenergiza tionof relay 35, relafvl ll denergizes, wherev uponfltheconnector and theline switch 0 are restoredto normal position in thewell known manner.

elf the line of substation A had been busy when called, the connector Hwould have'operatedto connect a lead from the busy signaling machine Q,with one sIde of the calling line, the side switch wipers being held inthe second'position for this purpose and to .prevent connection with thecalled line. -Upon perceiving the busy signal the callingsubscriber,understands-that he is te'mporarily unable to get'therequired connection and, accordingly, he replaces his receiver,whereupon the apparatus is restored to normal position as beforementloned.

Having described the operation of estab-- l1sh1ng a connection betweentwo substations, I will now describe the operations which take placewhen an attem t is ma de has been to connect with a substation whicdisconnected. It has been mentioned before that the ringersatsubstations A", A and A are adapted to respond, respectively, to ringingcurrents from generators R R and R, there being no substation on theline corresponding to generator R. Now v if No. 422 be called instead ofNo. 122, the connector H will be operated as before exceptthat inresponse to the first digit the wipers will be raised to the fourthlevel instead of the first level, resulting, accordingly, in theenergization'of relay 363 instead of relay 63. The connector is thenautomatically released as before and may be operated thereafter inaccordance with the remaining two digits to a ain connect with the lineconductors 76 an 79. Now,,how-

ever, when the ringing operation begins, ringing current from generatorR is Y87', and side switch wi er 30 (in third po-' sition) to battery B.twill be seen that relay 87, when energized, connects the heavy talkingconductors of connector H with the traflic trunk conductors 99 and 199which extend to an operators position. The relay 200, in bridge of thetraffic trunk, is now.

energized in series with the back bridge relay 36, thereby stopping theringing opera tion as previously described and lighting the lamp signalL. The operator, being informed by the glowing of the lamp that a callhasbeen received, may bridge her head set (not shown) across the trunkconductors by means of the key K and is then able to converse with thecalling subscriber. After having received the appropriateinformation,the calling subscriber will understand that he cannot getthe required party and he will therefore replace his receiver, whereuponthe apparatus is restored to normal position in the regular manner.

It will be understood that while my 1mproved system of selective ringingand my improved method of giving traffic trunk service are particularlyadapted for use in combination with each other, there is no suchinherent deipendency between the two as would preclu e the use of eitherfeature separately or in combination with other systems directed" to thesame general objects.

It will be understood, furthermore, that.

various changes may be made in the exact disclosure shown herein for thepurpose'of adapting my invention for use in connection with other typesof apparatus.- I desire to include, therefore, and have protected byLetters Patent all forms and modifications of my invention which shallhereafter be devised, limited only by the scope of the ap ended claims.

What I claim as my invention is:

1. In a telephone system, a party line connector switch responsive to aplurality of digits in a called number, party lines and se- I lectableterminals therefor in said connector,

party lines, sources of ringing current of.

different character for signaling substati'ons on said linesselectively, and means in said connector responsive to one of saiddigits for selecting one of said sources before selectin any 'of saidterminals, said means inclu ing an operating magnet for said switchcontrollable thereafter in response to another digit for the selectionof certain of said li'ne terminals, the circuit for said operatingmagnet excluding the talking circuit.

3. In a telephone system, a party line connector switch responsive to aplurality of digits in a called number, party lines and selectableterminals therefor in said connector, sources of signaling current ofdifferent character, and electro-magnetic means for operating saidswitch,said means responsive to one of said digit's for selectmg one ofsaid sources independent of any selection of-said terminals andresponsive thereafter to one or more digits for selectmg the terminal ofone of saidparty lines.

4. In a telephone system, a party line connector switch responsive to aplurality of digits in a called number, party lines and selectableterminals therefor in said connector, sources of signaling current ofdlflerent character, electro-magnetic means for operating said switch,said means responslve to wed said digits for selecting one of saidsources independent of any selection of said terminals and responsivethereafter. to one or more other digits for selecting the terminal ofone of said party lines, a pluralit of substations in bridge ofeach ofsaid lines, signals at said stations corresponding to said differentsources of signaling current, and means for connecting a selected sourcewith a selected line to signal a wanted substation thereon.

5. In a telephone system, a party line connector switch and an operatingma therefor, a plurality of party lines divided into grou 5, each linehaving a terminal in said switc a plurality of sources of signalingcurrent of different character for signaling substations on said linesselectively, a controlling circuit for said magnet, means controlled bysaid magnet in response to a series of current impulses produced in saidcircuit for selecting one of said sources, and means controlled by thesame magnet in response to another series of current impulses gnetproduced in said circuit for selecting a groug of said lines. 7

6. n a telephone system, a party line connector switch and an operatingmagnet therefor,a plurality of party lines each havin 'a terminal insaid connector, said termi-- na s arranged in groups, a plurality ofsources of signalin current of different character for signalingsubstations on said lines selectively, a controlling circuit for saidmagnet, means for producing series of current impulses in said circuitfor operatingsaid' magnet, means controlled by said magnet in. responseto one series of impulses for selecting one of said sources and a groupof terminals simultaneously, and

means for automatically releasing said switch only in so far as saidgroup selection is concerned, whereby the same or another terminal groupmay be selected thereafter 4 in res onse to another series of impulses.

n a telephone system, a connector switch, a plurality of lines havingterminalsin said connector arranged in groups, a plurality of signalingcircuits associated with said connector, an operating magnet for saidconnector, means controlled by said magnet for closing one of saidcircuits,

means for releasing said switch and forv maintaining said circuitclosed" after the switch is released, and means controlled by saidmagnet thereafter for selecting one of said groups of line terminals,whereby any one of said circuits may. be closed and any one of saidgroups maybe ,selected contemporaneousl 8. In a telephone systemcomprising party lines, a connector switch, a multiple terminal for eachline in said switch, sources of signaling current of difli'erentcharacter for calling substations on said lines selectively,

means for operating said connector in accordance with a digit of acalled number to 'eifecta selection of one of said sources and of one ormoreof said lines, and means for nullifying the effect of such operationupon the line selection, whereby said connector may be operatedthereafter inaccordance with one or more other digits of the'callednumber to select a called line.

9. In a telephone system comprising party lines, a connector switch, amultipleterminal for each linein said switch, sources of signalingcurrent of different character for calling substations on said linesselectively, means for operating said connector in accordance with adigit of a called number to effect a selection of one of said sourcesand of one or more of.said lines, and means for releasing said connectorin 'so far as concerns the line selection, whereby it may be operated.in accordance with one or more other digits of the called number toselect a wanted line. p

10 In a. telephone system comprising party lines, a connector switch, amultiple terminal for each line in said switch, sources of signalingcurrent of different character for calling substations on said linesselectively, means for operating said connector in accordance with a'digit of a called number to effect a selection of one of said sourcesand of one or more of said lines, means for nullifying the effect ofsuch operation upon the line selection, whereby said connector maybeoperated thereafter in accordance with one or more other digits of thecalled number to select'a called line, and means for connecting aselected source with a'selected line to signal a wanted substationthereon.

11. In a telephone system comprising party lines, a connector switch, amultiple terminal for each line in said switch, sources of signalingcurrent of different character for calling substations on said linesselectively, means for operating said connector in accordance with adigit of a called numher to effect a selection of one of said sources.

and of one or more of said lines, means for releasing said connector inso far as concerns' the line selection, whereby it may be operated inaccordance with'one or more other digits of the called number to selecta wanted line, and means for connecting a selected source with aselectedline to signal a wanted substation thereon.

12. In a telephone system, a plurality of. party lines each having aplurality of substations, a connector switch having vertical and rotarymovements and containing a multiple terminal for :each of said lines,sources of ringing current of different character for signaling thesubstations on a line selectively, means operated by the first verticalmovement of said switch for selecting one of said sources, automaticmeans for releasing said switch thereafter while retain- "multipleterminal for each of said lines and having a plurality of operatingmovements ing the selected source in selected condition,

and means effective upon further operation of said switch for connectingthe selected source with one of said lines to signal a wanted substationthereon.

13. In a telephone system, a plurality of party lines each having aplurality of substations, a connector switch containing a -thereon.

r 14. In atelephone system, a plurality of party lines, a connectorswitch having vertical and rotary movementsfor selecting a wanted line,a plurality of sources of signaling currents of different character forsignaling substations on said lines selectively, a relay for each sourcefor extending the same to said connector, contacts for said relaysarranged in a vertical row, a wiper adapted to engage said contactssuccessively in the vertical movement of said switch, and means foroperating said switch to operate one of said relays through the mediumof said wiper and one of said contacts. l5. In a telephone system, aplurality of party lines, a connector switch having vertical and rotarymovements for selecting a I wanted line, a plurality of sources ofsignaling currents of different character for signaling substations onsaid lines selectively,'a relay for each source for extending the sametosaid connector, contacts for said relays arranged in a vertical row, awiper adapted to engage said contacts successively in the verticalmovement of said switch, means for operating said switch to operate oneof said relays through the medium of said wiper and one of saidcontacts, and means for releasing said connector thereafter and formaintaining the selected relay energized, whereby upon further operationof said switch to select a wanted line the source Selected by theoperated relay may be connected with the said line to signal aparticular substation thereon.

16. In a telephone system, a plurality of party lines each havingsubstation signals responsive to signaling currents of differentcharacter, sources of signaling current of different character, acalling line, a con vnector switch accessible to said calling line and aprogressively movable wiper, means in said connector for. o crating saidwipers simultaneously; for se ectively associating said sources with acalled line in accordance with a called number, a trunk to an-operatorsposition, and means associated with said connector for connectin thecalling line with said trunk should t e substation corresponding to thecalled number be disconnected, said first means including a magnet whichis operated by two series of impulses during the same call for operatingsaid progresslvely movable wiper.

17. In a telephone system, a plurality of party lines each havingsubstation signals responsive to signaling currents of differentcharacter, sources of signaling current of different character, acalling line, a connector switch accessible to said calling line forextending connections to said lines,

means in said connector for selectively associating said sources with acalled line. in accordance with a called number, a trunk to an operatorsposition, means associated with said. connector for connectingthecalling' line with said trunk, and means for preventing "connection withsaid trunk when .the substation corresponding to the called number is inservice.

18. In a telephone system, a party line and a plurality of substationsin bridge thereof, each substation having a signal responsive to aparticular character of ring ing current, different sources of ringingcurrent corresponding to said signals, a callin line, a connector switchfor extending said calling line to said party line, line and test wipersand a progressively movable wiper for said connector switch, means insaid connector for operating said wipers simultaneously for connecting aparticular source of ringing current with said party corresponding tosaid signals, a callin line,

a connector switch for extending sai 1 callingline to said party line,means in said connector for connecting a particular source of ringingcurrent with said party line to signal a wanted substation, a trunkextending to an operators position, means associated with said connectorfor extending the calling line to said trunk, and means responsive to.the actuation of the signal at the called substation for preventing theoperation of said second means.

, 20. In a telephone system, a party line and a plurality of substationsin bridge thereof, each substation having a signal re- I sponsive to aparticular character of ringing current, different sources of ringingcurrent corresponding to said signals, a callin line, a connector switchfor extendingsai calling line to said party line, means in saidconnector for connecting a particular source of ringing current wit saidp arty line to signal a wantedsubstation, atalking branch of saidconnector extending to an operators position, means for closing saidbranch 1f the wanted substation is dlsconnected from said line and meansfor preventing the closure oi tion is connected to sald line.

said branch if thewanted substa- 21. In a telephone system, a substationand a line therefor, a signal at said substation responsive to aparticular character of rin ing current, sources of ringing current ofifi'erent character, a calling line, a connector switch for extendingthe said calling line to said first line and for connecting said sourcesthereto selectively, a trunk line extending to an operators position,means for connecting the calling line thereto, and

means for preventing such connection when the particular ringing currentsource corresponding to the substation on said line has been connectedtherewith.

22. In a telephone system, a substation and a line therefor, a signal atsaid substation responsive to a particular character of ringing current,sources of ringing current of difi'erent character, a calling line, aconnector switch for extending the said callin line to said first line,and for connecting said sources thereto selectively, a talking'branch ofsaid connector extending to an operators position," means for closingsaid branch after said lines have been connected, and

means for preventing the closure of said branch should the particularsource have been selected which is adapted to actuatesaid si a1. i

23. n' a telephone system, a substation and a line therefor, a signal atsaid substation responsive to a particular character of' Iringingcurrent, sources of ringing current of different character, acalling line, a connector switch for extending the said calling line tosaidfirst line and for connecting said sources thereto selectively, anormally disconnected talking branch of said connector extending to anoperators position, means for closing saidbranch, and means dependentupon the actuation of the signal at said substation for preventing theclosure ofsaid branch.

24. In a telephone system, a substation' and a lineftherefor, a signalat said substa- 1so I rasaavo tion responsive to a particular characterof rm g current, sources of ringing current of dil ferent character, acalling line, a connector switch for extending the calling line intoconnection with said first line, means in said connector for connectin aparticular one of said sources with said rst line to actuate saidsignal, a normally disconnected talking branch of said connectorextending to an operators position, a relay for closing said branch,means for preventing. the op.

eration of said relay during the signaling operation, and means actuatedupon the reonse ofthe called subscriber for stopping t e signalingoperation and for preventing the operation of said relay thereafter.

'25. In a'telephone system, a plurality of substations and linestherefor, a signal in bridge of the line at each substation, said bridgeinsulated to direct currents, a connector switch for connecting acalling and a called one of said lines, a source of signal ing current,a source of direct current, a branch extending from talking conductorsof said connector to an operators position, means for closing saidbranch, means in said connector for completing a signaling circuitincluding a called line and said sources all in series, a relay in saidcircuit for preventing the closure of said branch, said relayirresponsive to signaling current, and means at each substation forclosing a direct current bridge across said line when the signal thereatis actuated, whereby said relay may be operated.

26. In a telephone system, a party line and a plurality of substationsin bridge thereof, each substation having a signal responsive to aparticular character of ringing current and each substation normallyinsulated to direct current flow over said line,

different sources of ringing current corresponding to said signals, aconnector switch for completing connection to said line, a normallydisconnected branch extending from the talking conductors of saidconnector to an operators position, a relay for closing said branch,means in said connector for selectively connecting said sources withsaid line to actuate said signals, a source of direct current and asecond relay in series with said rin ing current source when soconnected, sai second relay irresponsive to ringing currents, meanscontrolled by said second relay for preventing the operation-of saidfirst relay, and means for closing a direct current bridge across saidline when one of said signals is actuated to thereby opcrate said secondrelay.

27. In a telephone system, a plurality of lines, substation signals inbridge of certain of said lines, said bridges insulated to directcurrents, a connector switch for completing connections to said lines, asource of signaling current and a source of direct current, means insaid connector for completing a signaling circuit, including a calledrtors position, means for closing saidbranch, a relay in said signalingcircuit for preventing the closure of said branch, said relayirresponsive. to signaling current, and means at each substationcontrolled by the signal thereat for closing a direct current bridgeacross its associated line to operate said relay, whereb the closure of'said branch-is made to epend upon whether or pot'the called line has aconnected substa- 28. In a telephone system, a pl"'ality of lines eachhavlng a substation in bridge thereof, a plurality of other lineswithout substations, a connector switch for completing connections tosaid lines, a normally disconnectedbranch extending from talkingconductors of said connector to an operators position, means forautomatically closing said branch when connection is completed to a linewithout a substation, and means for preventing the closure of saidbranch when connection is completed to a line with a' substationin'bridge thereof;

29; In a telephone system, a plurality of substations and lines thereforextending to an exchange, a plurality of other lines without substationsalso terminating at said exchange, a connector switch accessible to acalling line of said first plurality for extending connection to any oneof said firstor second pluralities, a normally disconnected branchextending from talking conductors of said connector to an operatorsposition, means for closing said branch when connection is completed toa line of said second plurality, whereby the calling line is extended tothe said operators position, and means for preventing the closure ofsaid branch when connection is completed to a line of said'firstplurality.

30. In a telephone system comprising party lines, a connector switch, amultiple terminal for each line in said switch, sources of signalingcurrent of different character for calling substations on said lineselectively, means for operating said connector in accordance with adigit of a called number to eflect a selection of one of said sourcesand of a group of said lines, and means for nullifying the effect ofsuch, operation upon the line selection, whereby said connector may beoperated thereafter in accordance with one or more other digits of thecalled number to select a called line.

31. In a telephone system comprising party lines, a connector switch, amultiple terminal for each line insaid switch, sources of signalingcurrent or different character for the calling substations on said linessenector in accordance with a digit of a called number to eiiectaselection of one of said sources and of one or more of said lines, andmeans for nullifying the efiect of such operation upon the lineselection, whereby said connector maybe operated thereafter inaccordance with a plurality of other digits of the called number toselect a called l'ne.

l 32. In a telephone system comprising party lines, a connector switch,a multiple terminal for each line in said switch, sources of signalingcurrent of different character for calling substations on said linesselectively, means for operating said connector in accordance with adigit of a called number to effect a selection of one of said sourcesand of a group of said lines, means for nullifying the effect of suchoperation upon the line selection, whereby said connector may beoperated thereafter in accordance with one or more other digits of thecalled number to select a called line, and means tively,

. for connecting for connecting a selected source with a selected lineto signal a wanted substation thereon.

33 In a telephone system comprising party lines, a connector switch, amultiple terminal for each line in said switch, sources of signalingcurrent of different character for calling substations on saidlines-selecber to effect a'selection of one of said sources and of oneor more of said lines, nullifying the effect of such operation upon theline selection, whereby said connector means for operating saidconnector in accordance with a digit of a called mun-I means for may beoperated thereafter in accordance with a plurality of other digits ofthe called number to select a called line, and means' a selected sourcewith a selected line to signal a wanted substation thereon.

Signed by me at St. Paul, Ramsey county, State of M1nn-., this 1st dayof March, 1916.

HARRY E. HERSHEY.

